Document Type: Research Articles
Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
Center of Excellence for Innovation in Chemistry, Cholangiocarcinoma Research Institute, Cholangiocarcinoma Screening and Care Program (CASCAP), Faculty of Medicine, Khon Kaen University, Khon Kaen,Thailand.
Center of Excellence for Innovation in Chemistry, Liver Fluke and Cholangiocarcinoma Research Institute, Cholangiocarcinoma Screening and Care Program (CASCAP), Faculty of Medicine, Khon Kaen University, Khon Kaen,
Natural Products Research Section, Research Division, National Cancer Institute; Bangkok, Thailand.
Cholangiocarcinoma is a malignant tumor with high metastatic and mortality rates. We investigated the effects
of rhinacanthin-C on cell proliferation, migration, invasion and the expression of proteins regulating cancer cell
invasion-regulated proteins in a cholangiocarcinoma (KKU-M156) cell line. Cytotoxicity of rhinacanthin-C was
determined by the SRB assay. Using wound-migration, chamber-migration and chamber-invasion assays, we assessed
the effects of rhinacanthin-C against KKU-M156 cells. The activities of matrix metalloproteinases 2 and 9 (MMP-2,
MMP-9) and urokinase-type plasminogen activator (uPA) were determined using gelatinase and uPA zymography
assays. The expression of invasion-regulated proteins was investigated using western-blot analysis. After treatment
with rhinacanthin-C, KKU-M156 cells exhibited antiproliferative effects in a dose-dependent manner with greater
efficacy than in Vero cells: IC50 values were 1.50 and 2.37 μM, respectively. Rhinacanthin-C significantly inhibited cell
migration and invasion of KKU-M156 cells in a dose-dependent manner. Consistent with this observation, treatment
with rhinacanthin-C was associated with a decrease in the expression levels of FAK, p-FAK, MMP-2, and a decrease in
the levels of p38-, JNK1/2- and ERK1/2-MAPK pathways as well as inhibiting NF-κB/p65 expression and translocation
of NF-κB/p65 to the nucleus. We have shown for the first time that the anti-metastatic effects of rhinacanthin-C on
KKU-M156 cells are mediated via inhibition of the expression of invasion-regulated proteins. Rhinacanthin-C may
deserve consideration as a potential agent for the treatment of cholangiocarcinoma.